| Abstract:Black liquor is always treated by traditional alkali recovery method in which the biomass including lignin is burned to reduce the organic pollutants; and a large amount of CO2 and other harmful gases are generated while generating sodium carbonate. In order to solve this problem， a new method was developed to treat pulping black liquor. The process included five steps: acidified precipitation（A）， desalination by frozen crystallization（D）， upflow activated sludge bed（UASB）， reverse osmosis filtration（RO） and electrolysis（E）. The experimental results ware, the yield of lignin was 28.09% of the mass of the black liquid， the alkali production rate was 2.38 g /（h·L）， when electrolytic for 24 hours， the alkali recovery rate of sodium sulfate was 50.64%，the electric energy consumption was 1.598 kWh per 1 kg of sodium hydroxide. |
